I have limited knowledge on Holleys, but I had a 650 on my built 302 and experienced the same conditions as you regards to running and strong gas smells. What I did was take the top off the carb and found dirt and metal shavings in the float bowls (I ran the carb for about a month with no fuel filter when I finished the car, I know it was stupid
). The rear float was also a little high and I adjusted that as well, since it would leak into the carb after shutdown in the back bores. The car ran great after I did that. I never had the powervalve go, but sounds like you will be checking that.
I'm sure you'll get other responses with more experience, but that's what we're here for!